Well casing attachment



March 30, 1937.

'JIJ. LARKIN WELL CASING ATTACHMENT 3 Sheets-Sheef 1 Original Filed March 19, 1930 63ml 1/0 a: ZAR/r/A/ 65 3 WWW March 30, 1937. J. J. LARKIN WELL CASING ATTACHMENT Original Filed March 19, 1950 3 Sheets-Sheet 2 March 30, 1937. J. J. LARKIN WELL, CASING ATTACHMENT.

Original Filed March 19, 1930 3 Sheets-Sheet 3 v (/Ol-l/V J. 1.4 Elf/N Patented Mar. 30, 1937.

WELL CASING ATTACHMENT John J. Larkin, St. Louis, Mo.

Application 4 Claims.

This invention relates to well casing attachments more particularly of the type adapted for rotary drilling. Such attachments. are shoe guides, float and cement shoes and float collars.

In the use of these attachments, it is necessary that the drilling be carried on therethrough. This is true even though the attachments are provided with inwardly projecting parts and even with valves. As a typical example in the cement-' ing of a casing, a cement shoe is coupled to the end of the casing and let down into the well and cement is then pumped into the casing and up the outside thereof so as to cement the same in the well. It has heretofore been the practice to have a destructive effect on the bit. Moreover, the effect of the bit is rather a crushing than a grinding action on cast iron, so that the cast iron is liable to break up into large fragments which I are difficult to remove.

In rotary drilling, a mud laden fluid is pumped through the drill stem and withdrawn through the casing, the mud issuing from the well being allowed to settle in a suitable ditch, in order to deposit the cuttings, after which it is again pumped back into the well. Now, cast iron, on account of its high specific gravity and its tendency to break up into large fragments, is difflcult to remove; this is for the reason that, on account of these characteristics, it is diflicult to keep it in suspension or within the body of the mud laden fluid, unless such ,mud laden fluid is viscous and thick. A thick mud is, however, not only difficult to pump, but is liable us become gas-cu that is, filled with bubbles of gasthereby causing its specific gravity to be lowered to such an extent that heavy pressures cannot be kept down.

One of the objects of this invention, therefore, is to provide a casingattachment of the character described, which overcomes the objectionable features referred to above.

Another object is to improve casing attachments of the character described, so as to simplify and render the same more economical in practice. Further objects wiil appear from the detail March 19,1930, Serial No. 437,015 Renewed July 29, 1935 description, taken in connection with the accompanying drawings, in which Figures 1 and 2 are respectively a vertical section and an end view of a casing shoe and guide embodying this invention.

Figures 3 and 4 are similar views illustrating another embodiment of this invention.

Figures 5 and 6 are similar views showing the features of the present invention as embodied in a float collar.

, In the use of casing attachments of the character hereinbefore referred to it sometimes happens that a part, such as a valve or other comparatively large part will become loose and drop into the casing. In accordance with the present invention suitable means is provided for preventing such a loose part or object from lodging-in such a position within the attachment that the flow of fluid, such as mud, cement or water is interrupted. By thus preventing such falling objects from blocking the passage through such that this invention is susceptible of various other embodiments and applicable to various other casing attachments.

Referring to Figures 1 and 2, which illustrate a float shoe, a casing shoe I is threaded, as shown at 2, in order to enable its attachment to a casing. The shoe is provided with a passage therethrough in which may be arranged a valve in the manner hereinafter set forth. In the particular embodiment shown, the end of the shoe has threaded therein a connection 6 on a guide l. Attached to or formed integral with this guide, is .a part 8; connected to this part 8, as by threading, is another part 9. The parts 8 and 9 are provided with a passage, and the part 9 is provided with a valve seat l0 and a guide IE. Cooperating with the valve seat is a downwardlyv opening valve l2 having its stem. l3 working in the guide It and provided with a spring l4 hearing at one end against the guide and at the other end against a head 15 thereon.

The parts 8, l, 8 and 9 may be constructed of a low specific gravity metal, such as aluminum, its alloys, or magnesium all0ys, and the valve parts 52, i3 and 55 may also be constructed of this metal. The spring id may be constructed of springy brass or bronze. The space between the body or shoe E and the parts 6, E, ii and t is preferably filled with a ping of filling matemal it,

composed of any suitable cementitious material, such as a Portland cement-sand aggregate.

It will be seen that this provides a float shoe in which the interior is formed of a material which is readily operated upon by the bit. The aluminum parts,-being of low specific gravity and of a metal breaking up into small particles, can not only be readily removed from the well, but can be readily disintegrated, while producing particles which are not abrasive. The filling can also be readily broken up. It will be understood, of course, that the parts 8 and 9 can be provided with suitable lugs or projections l1 .to bond with the filling, while the interior of the'shoe can be roughened or threaded, as shown at IQ, for the same purpose. The interior of part 8 may, moreover, be re-enforced with suitablewebs I8.

Referring now to Figures .3 and 4, this construction is similar to that shown in Figures '1 and 2, so that similar parts have been indicated by like reference numerals. In this embodiment, however,parts 6 and J are omitted, and the filling plug l6 extends beyondthe shoe I, so as to provide the guide as shown at 20. In this case, additional lugs 2| may be provided, in order to effect the desired bond. 1

Referring now to Figures 5 and 6 for an illustrative embodiment of the present invention in a float collar, a tubular float collar member 22 is provided with threads 23 enabling its attachment to casing sections. Float collar 22 may be provided with an interior part I2 having a seat 33 and a guide 34. A valve 35 cooperates with the seat and has a stem 36 passing through the guide and provided with a spring 42, bearing at one end against the guide 34 and at its other end against a nut 31 on the stem. The valve, its stem and nut, may, again, be of the same.metal as the interior part 32, while the spring may be of springy brass or bronze. In this embodiment, a filling plug 38 of cementitious material, as here tofore described, is provided between the collar 22 and the interior part 32, the collar being suitably roughened as shown at 39, while the interior part is provided with lugsas shown at 40', in order to bond the two together.

-- In each of the. embodiments hereinbefore described the passage through the interior of the device is provided with a flaring mouth formed by laterally extending channels H at the top vof the plug of filling material (it of Figures 1 and 3,

' 38 of Figure 5). By providing a number of such channels arranged radially and opening into the passage suiiicient opening area canbe left so that the flow will not be interrupted even though a body or part entirely close the mouth of the vertlcal passage. With this arrangement of parts the portions of the plug of filling material between lateral channels ll, being disposed radially inward of the outer confines of the large mouth provided by channels 4| and also extending above the bottom of said channels 4|, are in position the high column of water, mud or cement, will be carried by one valve. In accordance with this invention, therefore, and as shown in Figure 5, the valve 35 is provided with a port arranged to be closed by a plug 42, which plug can be removed. In this way, by taking out one or more plugs from one or morevalves, the pressure can be carried by any desired float collar, as this provides a relief at any desired point,

It will be seen that the provision of a machined valve (such as i2 and 35), provided with a stem, mounted in a bearing and seating against a definite machined seat, enables a water-tight joint to be secured, even though the filling of the attachment to be drilled out is of cement. Such a structure hasa distinct advantage over one in which the valve is in the form of a ball, especially when the latter must be formed oi a material which will float. Such a ballwill not only fail to seat properly, but may swell or break, causing not only failure to hold pressure, but it is liable to break and pass on so as to clog another passage along the casing.

It will be understood that certain features and sub-combinations are of utility and may be employed without reference to other features and sub-combinations; that is contemplated by and are within the scope of the appended claims. It

will furthermore be understood that various changes may be made in details within the scope of theappended claims without departing from the spirit of this invention. It is therefore understood that this invention is not to be limited to the specific details shown and/ordescribed.

Having thus described the invention, what is claimed is:v

l. A casing attachment of the character tie-- scribed comprising, a tubular body adapted for coupling to a casing, a cylindrical plug within said body, an axial longitudinal passage through said plug, and a transverse channel in the top of the plug which leads to the passage.

2. A casing attachment of the character described, comprising, a body adapted for coupling to a casing, said body having a passage therethrough provided with a seat, a movable valve in said passage and engaging with said seat, said valve being provided with a port, and a removableplug for closing said port.

3. A casing attachment comprising, a tubular body adapted for coupling to a casing, a plug in said body, said plug having a passage therethrough with an enlarged mouth adjacent the top of said plug, a valve in said passage arranged to open to permit fluid to flow therethrough from above and means extending above the juncture of said passage and said enlarged mouth to support a fallen object clear of said passage.

4. A casing attachment comprising, a tubular body adapted for coupling to a casing, a plug in said body, said plug having a passage therethrough with a radially enlarged mouth adjacent the top of said plug, a valve in said passage arranged to open to permit fluid to flow therethrough from above and means disposed radially inward oi the outer confines of said mouth and elevated above the bottom of said mouth to support a fallen object-clear of said passage.

'Jorm J. mm. 

